At maximum speed, an airplane travels 1720 miles against the wind in 5 hr, the plane can travel the same distance in 4 hr let x be the maximum speed of the plane and y be the speed of the wind. what is the speed of the plane with no wind?

387 miles / hour

Step-by-step explanation:

X be the maximum speed of plane and Y be the speed of wind.

Speed is the ratio of distance traveled to the time taken by the body.

When the plane travels against the wind, the speed of the plane is X - Y and when the plane is moving with the wind the speed is X + Y.

According to the formula

speed = \frac{distance}{time}speed=timedistance

X - Y = \frac{1720}{5}X−Y=51720

X - Y = 344 (1)

And

X + Y = \frac{1720}{4}X+Y=41720

X - Y = 430 (2)

Adding both the equations,

2X = 774

X = 387 miles/hour

x > 1.3

step by step:

8.5−0.9x> 9.8−1.9x

step 1: simplify both sides of the inequality.

−0.9x+8.5> −1.9x+9.8

step 2: add 1.9x to both sides.

−0.9x+8.5+1.9x> −1.9x+9.8+1.9x

1x+8.5> 9.8

step 3: subtract 8.5 from both sides.

1x+8.5−8.5> 9.8−8.5

1x> 1.3

step 4: divide both sides by 1.

1x/1 > 1.3/1

the answer is (-4,-4)

hope this ! : d